Method and apparatus for correction of non-impact printing

Abstract

A method and apparatus for correction of non-impact printed material which is formed by depositing a thermoplastic marking material on the print sheet. The method and apparatus uses a correction tape or ribbon comprising a substrate which carries a pressure transferable pigmented material on one face. The correction ribbon is positioned between the erroneously printed character and a correction device which is actuated to produce sufficient pressure to move the correction ribbon into intimate contact with the erroneously printed character, and the pigmented material is transferred selectively only to the character area to cover the erroneously printed character, so that the correct character can then be printed. In an alternate embodiment, the correction device is actuated concurrently with a backspace operation.

Having thus described our invention, what we claim as new, and desire to secure by Letters Patent, is: 
     
       1. A method for correcting non-impact printed data a character at a time comprising the steps of: printing the characters with a printing head utilizing a non-impact printing technique which deposits a detectable thickness of thermoplastic marking material on a record medium;   providing a corrective ribbon which carries a pressure transferable opaque adherent pigmented material on one surface thereof;   interposing said corrective ribbon between said record medium and said printing head;   positioning the character to be corrected into an impressing position; and   selectively producing pressure to move the corrective ribbon into intimate contact over an area registering with the incremental area of said record medium containing the printed character to be corrected, so that the opaque adherent pigmented material is transferred only to the character to be corrected.   
     
     
       2. The method of claim 1 wherein said positioning step comprises a backspacing operation. 
     
     
       3. The method of claim 2 wherein said step of selectively producing pressure is accomplished after the positioning step. 
     
     
       4. The method of claim 2 wherein said step of selectively producing pressure comprises advancing a correction device into contact with the corrective ribbon prior to the backspacing operation; and maintaining said correction device in contact with said corrective ribbon during said backspacing operation.   
     
     
       5. A method for printing data on a record medium in which wrongly printed characters are corrected, a character at a time, by obscuring the wrong character and over-printing the correct character, characterized in that the characters are printed using a non-impact printing technique which deposits a detectable thickness of thermoplastic material on a record medium and in that a wrong character is obscured by positioning adjacent the wrong character a layer of pressure transferable opaque adherent pigmented material carried on one surface of a corrective ribbon and selectively producing pressure relatively to move the corrective ribbon into intimate contact with the wrong character so that the opaque adherent pigmented material is transferred only to the wrong character.